1. Field of the Invention
This invention relates to a reclining device adapted to be attached to a vehicle seat for adjustably controlling the position of the seat back and more particularly, to a novel and improved reclining device which incorporates a differential reduction gearing mechanism having internal and external gears which have the same pitch but differ in the number of teeth and which are adapted to engage and disengage from each other as an eccentric shaft rotates.
2. Description of the Prior Art
There have been proposed and practically employed a variety of reclining devices for attachment to vehicle seats and one typical prior art reclining device of this type comprises a differential reduction gearing mechanism interposed between a bracket associated with a vehicle seat cushion and a bracket associated with a vehicle seat back and incorporating internal and external gears which have the same pitch but differ in the number of teeth and which are adapted to engage each other through an eccentric shaft so that the inclination position of the seat back can be adjusted steplessly.
However, such a prior art reclining devices have been proved inconvenient by the fact the when that inclination position of the seat back is substantially adjusted or the seat back is inclined forwardly, the eccentric shaft has to be rotated many times. The inconvenience of the prior art reclining devices is especially conspicuous when the reclining devices are employed in connection with a two-door type vehicle where an occupant has access to the rear seat only while the front seat is inclined forwardly.